Warp let-off for narrow-ware looms



nec. 2, 1921. 1,511,510

- E. R. HOLMES ET AL v WARP LET-OFF FOR NARROW WARE LOOMS Filed Anil 2.9. 1922 Patented Dec. 2, 1924.

UNITED kSTATES PATENT y ELBvRIDGE R. HOLMES AND ALLAN S. HU'1(`JH".1NS, 0F yY/VORCIElS'lllll'x., MASSACHUSETTS,

ASSIGNORS VTO CROMPTON & KNQWLES LOOM WORKS,'O'F WORCESTER, MASSACHU- SETTS, A CORPORATION F MASSACHUSETTS.

WARP LET-OFF FOR NARROW-WARE LOOMS. i

Application filed April 29, 1922. Seriell No. 557,385.

T0 all whom t may concern.

Be it known that we, ELBRIDGE R. HOLMES land ALLAN S. HU'rcHrNsboth citizens of the United States, residing at Worcester, in the county of Worcester and State of Massachusetts, have invented a new and useful )Varp Let-Off for Narrow-)Fare Looms, of which the following is a specification.v

This invention relates to a let-off `particularly designed for use in connection with narrow ware looms in which the warpfor a particular fabric is distributed on several warp beams or spools. In' order to produce a uniform and satisfactoryfabric, the 'tension upon all parts of the warp should be kept as nearly uniform as possib-le. yFor this4 purpose, it is customary to loopthe warp threads around weighted pulleys which have a considerable range of vertical to the warp. It is necessary, however, that fresh warp be let oftlfrom the spools at yfrequent intervalsandit is the object of our invention to provide improved mechanism under the control of the tension pulleys by which the warp spools maybe intermittently e releasedv to deliver warp to the'tensionpulle s.

yIn the preferred form of our invention, .the rotation of the spoolsv is retarded by engagement of a friction plate on each spool by a pair offriction pads pressed against the opposite faces of the plate.

An important feature of our invention relates to improved means for reducing or relieving the friction on the plate whenever rotation of the warp spool is desired. `A further feature relates to the provision of an improved construction by which removal of the warp spools is facilitated.

Our invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A. preferred fo-rm of our invention is shown in the drawings in which o Fig. 1 is a side elevation of a portion of a loom having our improved let-off vapplied thereto; f'

Fig. 2 is an enlarged front elevation of a portion of-one ofthe warp spools and its friction device Fig. 3 is an enlarged side elevation ofthe' parts shown in Fig. 2;

movement while applying, constanttension Fig. 4L yis a detail sectional view, taken along the line 4.--4 in Fig. 2; e

Fig. 5 is a detail sectional elevation, taken along the line 5 5 in Fig. 3; o

Figs; 6 and 7 kare side andfront elevations of the friction lever support, `to be described;

Fig. 8 is a detail rsectional. view, along the line 8-8 in Fig. 1, and

Fig. 9 is a detail rear elevation, looking in the 'direction ofthe arrow 9 in Fig. 1.

y Referring yto the drawings, we have shown a loom' side 10 having a warp frame 11 taken mounted vertically thereon. A plurality of warp beams or spools 12 are loosely` mounted on studs orpins 13 fixed in bars 14 pivoted at 15 to brackets 16 secured to the warp frame 11. At its lower end, each bar 14 is forked as indicated in Fig. 9 to receive a clamping bolt 17 (Fig. 1). By loosening` the bolt 17 and allowing the bolt to swing downward, any ybar 14 may be swung rearward to bring the spools 12 on vthat"particular bar out of alignment with the re-v` maining spools, thus permitting convenient removal andkreplacement thereof.

.The warp threads W on the spool 12 are passed'over rear guidek pulleys 18 and are then passed over a series of additional guide lpulleys 19. `Flach group or section of warp from which pointthey eXtendfoi-.ward to the'flay and reed.

The spools 12 may be ofany desired construction and are herein shownA as each having a steelbarrel 25 (Fig. 5) and 4disc-like steel heads 26. An opening 27 is formed in one of the heads `26 and is positioned to re ceiv'e'a headed stud 28 fixed in a (friction disc 29 rotatably mounted onv the pin, or studl. u

The opening 27 is large enough to admit the head of the stud 28 and the pull of the warp on the spool moves the stud to the relative forward position shown in dotted lines in Fig. 3, in which position the head of the stud prevents axial displacement of the spool. When the spool is to be removed,

however, it may be easily turned backward s sufficiently to center the head with the opening, permitting withdrawal thereof.

Each disc 29 is positioned between a pair of friction pads 30 and 31. The pad 30 is mounted on a bracket 32 (Fig. 2) fixed to the bar 14. The pad 31 is preferably formed in the shape of a ring as shown in Fig. 4, and is secured to the face of a lever 33 pivotally mounted on a stud or support 34 adjustably secured in the bar 14 by a setscrew 35. The lever 33 extends forward from its pivot and projects into the loop or frame 21 of the corresponding tension pulley20.

The support or stud 34 has a cylindrical shank engaged by the set screw 35 and a bearing portion or head provided with multiple screw threads ,36 of very steep pitch', seXtuple threads being shown in the drawings. The lever or arm 33' is threaded to fit the threads 36 and the stud 34 is provided with a screw-driver slot 37 by which it may be angularly adjusted. y

Having described the construction of our improved let-olf, the operation thereof is as follows: As the fabric is woven, each tension pulley 20 is gradually raised until the lower end of its loop frame 21 engages the corresponding lever `33. Up to this point, the lever 33, assisted if desired by a supplementary weight 38, hassupplied sufficient friction to the disc 29 to prevent rotation of the spool. As soon, however, as the lever 33 is engaged and moved upward by its tension pulley, its threaded support 84 'has a cam action on the lever to withdraw it slightly axially and thus reduce or release the friction on the disc 29. The remaining friction of the pad 30 is merely sufficient to lprevent free or idle rotation of the spool.

The spool thus released lets 'off a certain amount of warp, permitting Athe correspond ing tension pulley '2O -to descend. This movement frees the arm 180 andthe friction on the disc 29 is thus restored.

As it is found that a comparatively light weight on the lever 3S is Sufficient to hold,

spools A.to be used -on different portionsof the fabric in which different amounts of warp may be consumed and in which different warp tensions may be desired.

Particular attent-ion is called to the extreme compactness of the design, as indicated in Fig. 2. as the available space between adjacent sets of warp spools is very limited.

llVhile shown and described as applied to a narrow ware loom, certain features of our invention are also applicable to other types of looms, such as broad looms in which a fancy selvage is to be woven at the edge of the fabric.

Having thus described our invention and the advantages thereof, it will be evident that vchanges and modifications can be made* therein by those skilled in the art within the spirit and. scope of our invention as set forth in the claims, and we do not wish to be otherwise limited to the details herein disclosed, but what we claim is 1. In a narrow ware loom, a warp holder, means to frictionally resist rotation thereof, and means to intermittently release said holder, said Ifriction means including an ann gularly movable friction member, a fixed'` support for said member, said member and support having co-operatingcam surfaces, and warp controlled means to move said friction member angularly on its support, whereby the cam surfaces ofsaid support act effectively and directly on said yfriction member to withdraw said member from operative holding position relative to .said warp holder in a direction substantially perpendicular to the plane of angular movementv of said friction member.

2. In a narrow ware loom, Ya warp holder, means to frictionally resist rotation thereof, and means to intermittently release said This is of material importance holder, said friction means including an ani gularly movable friction member, a fixed support for said member, said member and support having co-operating multiple threads, and warp controlled means to move said friction member angulariy on said fixed' support thereby changing its axial. position thereon in a direction substantially perpendicular to the plane of angular movement yof said friction member and decreasing the frictional :resistance Aof said friction member against rotation of said warp hold er.

3. In a narrow waere inem, a warp holder, means to frictionally resist rotation thereof, Said friction means including .a fixed friction member, a disc :rotatable with said `warp holder and adjacent said ifixed member on one side, and azmova'ble friction .member effective to engage the opposite side'of Asaid disc and to .press the disc against said fixed yfrictiony member, .and warp :controlled means to intermittently withdraw said :movable `friction member zto release'the drag on said disc and warpholder,

4:.' In a narrow Ware loom, a plurality of taohably secured to the loom at their` free headed Warp spools, and e plurality of Verlower ends. tically extended supporting bars on which In testimony whereof We have hereunto 10 said spools are rotatably mounted, said bars aixed our` signatures. 5 being pivoted to swing rearwardly about the upper ends thereof and substantially in ELBRIDGE R. HOLMES. the plane of the spool heads'and being de- ALLAN S. HUTCHINS. 

